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bioRxiv · 10.1101/2019.12.17.879858

Enhancing generating and collecting efficiency of single particle upconverting luminescence at low-level power excitation

Ma, C.·Shan, C.·Park, K.·Mok, A. T.·Yang, X.
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Abstract

Upconverting luminescent nanoparticles are photostable, non-blinking, and low chemically toxic fluorophores that are emerging as promising fluorescent probe at single-molecule level. High luminescence intensity upconversion nanoparticles (UCNPs) is achieved with highly doped rare-earth ions co-doped (20% Yb3+) using high excitation power (>2.5 MW/cm2). However, such particles are inadequate for in-vitro live-cell imaging and single-particle tracking since high excitation power can cause photodamage. Here, we compared UCNPs luminescence intensities with different dopants concentrations and presented a more efficient ([~]7x) UCNPs at low excitation power by increasing the concentrations of Yb3+ and Tm3+ dopants (NaYF4: 60% Yb3+, 8% Tm3+) and adding a core-shell structure.

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Ma, C., Shan, C., Park, K., Mok, A. T., Yang, X.. 2019-12-18. Enhancing generating and collecting efficiency of single particle upconverting luminescence at low-level power excitation. https://doi.org/10.1101/2019.12.17.879858

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